简介:作为一种试验性的技术,它的需要在标本的温度在高温度裂口Hopkinson压力酒吧(SHPB)中是一致的,这试验。然而,当标本开始到时,在标本减少的温度和酒吧的温度增加与酒吧联系,它在标本导致不一致的温度分发,并且可以导致试验性的结果的不确。在这份报纸,当标本独自被加热时,在高温度SHPB实验的标本和酒吧的温度分布被调查。第一,标本的温度历史被实验在不同起始的温度测量,然后,模拟被执行。模拟结果与由调整在标本和酒吧之间的热接触系数的试验性的结果一致。由这样,热接触系数和模拟结果被验证,并且合适的冷接触在高温度SHPB实验标本和酒吧预定被讨论。最后,结果与在参考书的那些相比。
简介:TheresolutionexpressionforthetemperaturedependenceofthecurrentandthresholdvoltageisdeducedaswellastheanalysisoftemperaturecharacteristicsofBJMOSFET.EquivalentcircuitofanalysisandsimulationhasbeenestablishedfortheBJMOSFETtemperaturecharacteristics.ByusingthegeneralcircuitsimulationsoftwareofPSpice9andcomputersimulation,characteristicgraphsoftheBJMOSFEToutputcharacteristic,transientcharacteristicandamplitude-frequencycharacteristicwithtemperaturevariationareobtained.TheresultsaccordedverygoodwiththeoreticalanalysisandprovedthatBJMOSFEThasbettertemperaturecharacteristicsthantraditionalMOSFET.
简介:Inordertopredictthemechanicalperformanceofthepolyvinylchloride(PVC)atahighoperatingtemperature,aseriesofshort-termtensilecreeptests(onetenthofthephysicalagingtime)ofthePVCarecarriedoutat63Cwithasmallconstantstressbyadynamicmechanicalanalyzer(DMA).TheStruik-Kohlrausch(SK)formulaandStruikshiftingmethodsareusedtodescribethesecreepdataforvariousphysicalagingtime.AnewphenomenologicalmodelbasedonthemultiplerelaxationmechanismsofanamorphouspolymerisdevelopedtoquantitativelycharacterizetheSKparameters(theinitialcreepcompliance,thecharacteristicretardationtime,andtheshapefactor)determinedbytheagingtime.ItisshownthatthemomentarycreepcompliancecurveofthePVCat63CcanbeverywellfittedbytheSKformulaforeachagingtime.However,theSKparametersforthecreepcurvesarenotconstantduringtheagingprocessattheelevatedtemperatures,andtheevolutionoftheseparametersandthecreeprateversusagingtimecurvesatthedoublelogarithmiccoordinateshaveshownanonlinearphenomenon.Moreover,thecreepmastercurvesobtainedbythesuperpositionwiththeStruikshiftingmethodsareunsatisfactoryinsuchacase.Finally,thepredictedresultscalculatedfromthepresentmodelincorporatingwiththeSKformulaareinexcellentagreementwiththecreepexperimentaldataforthePVCisothermallyagedatthetemperaturerelativelyclosetotheglasstransitiontemperature.
简介:Oxygenisotopefractionationbetweencoexistingmineralsinslowlycooledrocksconveysinformationabouttheircoolinghistory.Byusingthefastgrainboundary(FGB)modeltosimulateclosed-systemdiffusiveexchangeofoxygenisotopesbetweencoexistingminerals,Ishowthattheapparentequilibriumtemperatures(Tae)bythemineralpairwiththelargestisotopicfractionation(PLIF)alwaysliesbetweentheclosuretemperatures(Tc)ofthosetwominerals.Therefore,whentherateofoxygendiffusionandhenceTcforthePLIFchancetobecomparable(suchasinthecaseofquartzandmagnetite),TaewillserveasagoodapproximationofTcregardlessofvariationinmineralproportions.ThespecialtyofthePLIFinconstrainingTaewithintheirTcrangecanbegeneralizedtootherstableisotopesystemsandelementpartitioning.ByapproximatingTcwithTaeandinvertingDodson'sequation,thecoolingrateofplutonicormetamorphicrockscanbeinferred.
简介:Theeffectoftemperatureonthecriticalaggregateconcentration(CAgC)hasbeeninvestigatedforthefirsttime,bymeasurementofthehydrolyticrateconstantsofp-nitrophenyldodecanoate(C12)andhexadecanoate(C16)atdifferenttemperaturesinthe30:70V/V(Φ=0.30)and40:60V/V(Φ=0.40)dioxane(DX)-H2Osystems.TheCAgCvaluesofC12andC16increasewiththeincreaseofthetemperature,i.e.,hightemperaturesdisfavoraggregation.ActivationenergiesforthehydrolysisofC12inthemonomericandaggregatedconcentrationdomainshavealsobeendiscussed.
简介:有1-hexene的乙烯的一系列共聚物综合了使用metallocene催化剂被选择并且混合。混合是经由准备温度升起的fractionatedelution分别(P-TREF)。所有部分经由高温度的胶化浸透层析(GPC)被描绘,<啜class=“a-plus-plus”>13C原子磁性的回声光谱学(<啜class=“a-plus-plus”>13C-NMR),并且微分扫描热量测定(DSC)。在作为elution温度的功能从P-TREF融化部分的山峰温度的DSC的变化是几乎线性的,从而提供TREF的elution温度通过试验的一本参考书能被选择。而且,P-TREF的标准刻度曲线(ethylene/1-hexene)被建立,它联系到部分的短链的分叉的度。P-TREF的标准刻度曲线是有益的在聚乙烯的复杂分叉结构上学习。为为TREF实验选择分别温度的一个方便方法被详细描述。聚乙烯样品是经由连续自我成核的fractionated并且退火(SSA)热分别。一个多重融化的温血动物通过在SSA热分别以后为样品加热扫描的最后的DSC被获得。一系列分别温度然后通过在融化山峰温度和TREFelution温度的DSC之间的关系被选择。
简介:ThispaperdealswiththetemperaturecorrelationofgrayscaleofBmodeultrasoundimagefromheatedtissue.Inthisstudy,manyin-vitrofreshpigliversareheatedinatemperaturerangefrom28℃to45℃,fromwhichaseriesofB-modeultrasonicimagesofliverswereobtained.Thegray-valueisevaluatedfromtheultrasoundimagesrespectively.Acorrelationofthemeangrayvalueoftheselectedregions(12×12pixels)inB-modeultrasonicimagesofliveranditstemperaturewaspointedout.Andtheexperimentresultsagreedtheevaluationwell.Anditispossibletomonitorthetissuetemperaturechanginginhyperthermiausingthiscorrelation.
简介:理解温度怎么在全球气候变化的背景下面在城市的上海变化并且它怎么被都市化影响,对全球温暖的上海温度回答被分析,然后温度趋势城市并且在不同气候的背景下面的郊区车站被获得。温度上的都市化效果被把城市的车站比作郊区车站学习,在都市化变量之间的关系和温度部件被获得,并且表面和高水平的观察数据被联合估计都市化效果的贡献。在纸的最后部分,温度上的都市化效果的原因被讨论。结果显示了:上海年度吝啬的温度的长期的变化趋势是从1873~2004的1.31/100a,1921-1948的时期并且1979-2004更温暖,并且1979-2004时期最温暖;与郊区车站相比,代表性的城市的车站在在温暖的凉爽的时期和更快的增加有更慢的减少;城市并且郊区温度有源于都市化和差别到一年正在增加的不同差别。与在秋天和在在城市、郊外的区域之间的夏天是最大的最大的温度的是最大的吝啬的温度和最小的温度的差别。都市化过程加速温暖的速度,与是最明显的最小的温度;都市化效果在1980年代贡献0.4~C增加并且我。在到年度吝啬的温度的1990年代的l~C。
简介:Atemperaturecontrolsystemof31mverticalforcedair-circulationquenchfurnaceisproposed,whichisakindofequipmentcriticalforthermaltreatmentofaluminumalloycomponentsthatarewidelyusedinaerospaceindustry.Fortheeffectiveoperationofthefurnace,itisessentialtoanalyzetheradialtemperaturedistributionofthefurnace.Asetofthermodynamicbalanceequationsmodelingisestablishedfirstly.Byutilizingthenumericalanalysisresulttomodifythetemperaturemeasurements,thecontrolaccuracyandprecisionofthetemperaturearetrulyguaranteed.Furthermore,themultivariabledecouplingself-learningPIDcontrolalgorithmbasedonthecharacteristicsofstrongcouplingbetweenthemulti-zonesinthelarge-scaledfurnaceisimplementedtoensurethetruehomogeneityoftheaxialtemperaturedistribution.Finally,theredundantstructurecomposedofindustrialcontrolcomputersandtouchpanelsleadstogreatimprovementofsystemreliability.
简介:Anewmethacrylamidemonomer,hexylaminemethacrylamide(MAHA),wassynthesizedandusedinpolymerizations.ThehomopolymerofMAHAanditscopolymersweresynthesizedbyfreeradicalpolymerizationtechniqueswithN-isopropylacrylamide(NIPAAm)intwodifferentcompositions.Thequaternizationofthehomopolymerandcopolymerswerecarriedoutusing1-bromopropane.ThecopolymerswithNIPAAmandalowMAHAcontentshowedtemperature-responsivebehaviorinanaqueousenvironment.Thelowercriticalsolutiontemperatures(LCSTs)ofthesepolymersvariedbetween32℃and44℃.TheLCSTsofquaternizedcopolymerswerehigherthanthoseofneutralcopolymersbecausetheyweremorehydrophilic.TheobtainedhomopolymersandcopolymersweretestedforantibacterialactivitiesagainstS.aureusandE.coli.Thequaternizedwater-solublecopolymersshowedantibacterialactivitiesagainstS.aureus.Thequaternizationresultedinthesynthesisofbothantibacterialandtemperature-responsivecopolymers.
简介:<正>Polyhalite(K2SO4·MgSO4·2CaSO4·2H2O)isoneoftheinsolublepotassiummineralwhichiswidelydistributedinsulfate-typepotassium-bearingdeposit,andthetheoreticalconcentrationofK2SO4is28%.Itcanbedirectlyusedasa
简介:SpecimensofPbTesinglefilmaredepositedonGesubstratesbyvacuumthermalevaporation.Duringthetemperaturerangeof80–300K,thetransmittanceofaPbTefilmwithin2–15μmismeasuredevery20KbythePerkinElmerFouriertransforminfraredspectroscopycryogenictestingsystem.Then,therelationshipbetweentherefractiveindexandwavelengthwithin7–12μmatdifferenttemperaturesisreceivedbythefullspectruminversionmethodfitting.ItcanbeseenthattherelationshipconformstotheCauchyformula,whichcanbefitted.Then,therelationshipbetweentherefractiveindexofthePbTefilmandthetemperature/wavelengthcanbeexpressedasn(λ,T)=5.82840-0.00304T+4.61458×10~(-6)T~2+8.00280∕λ~2+0.21544∕λ~4,whichisobtainedbythefittingmethodbasedontheCauchyformula.Finally,thedesignedvalueobtainedbytheformulaandthemeasuredspectrumarecomparedtoverifytheaccuracyoftheformula.
简介:Acousticimpulsesproducedthroughthemechanismofthelaser-inducedbreakdowninwaterhavebeeninvestigatedintherangefrom0℃toroomtemperature.Differentlyfromtheacousticimpulsesproducedviathermalexpansion,thepolarityandtheamplitudeofacousticimpulseproducedvialiquidbreakdownmechanismdonotchangewithwatertemper-ature.Thisindirectlyprovesthattheproductionofacousticimpulseisduetotheexpansionofthecavityitselfwhichincludesplasma.Asemiempiricaldescriptionofthisphenomenonisgiveninthispaper.